As disk drives continue to be reduced in size, the load beam or the beam which is used to hold and position a magnetic head in close proximity to the rotating disk in the disk drive also must be made smaller. The reduced size of the load beam makes attachment of the sliders more difficult than prior attachment techniques.
Further, as the disk drives are reduced in size, the recording density on the disks is greatly increased. These two factors, reduced disk drive size and increased recording density, not only dictate that the parts required for the disk drive assembly must be reduced in size, but also that the fly height of the small sliders must be further reduced from that of the previously known disk drives. The fly height reduction requires improved slider pitch and roll.
As recording density is increased, the vibrations of the slider tend to become more significant. The oscillations of the slider either must be eliminated or must cease prior to any read/write operations to allow the head to be stable as well as the slider to be in close proximity to the disk surface and track centerline to insure reliable recording and reading of the data stored on the disk.
As a further consequence of size reduction of the elements in the apparatus, the support members which hold and constrain the slider may be flexed beyond a predetermined amount; when so flexed, these support members may come into contact with the edges of the slider and effectively block the pitch and roll movement of the slider. To block the movement of the slider effectively creates a rigid member which may contact or impact the disk surface and may damage the disk surface and/or the slider structure.
The slider must be firmly attached to the load beam with even smaller attachment regions or zones. The attachment zones, therefore, must be maximized in order to insure that the attachment of the slider to the flexure of the load beam is effective and reliable. Also, maximizing the area of a bond is important in obtaining a reliable bond.
The wiring connected to the slider does resist pitch and roll movement of the slider. As the slider air bearing features are reduced in size, the effect of the electrical conductors of the wiring on the head becomes more significant as compared with other forces. The restraining influence of the wiring on the head with respect to its pitch and roll movement must be minimized, while at the same time the wiring must be positioned and restrained in such a manner which will resist the wiring being pulled from the slider, thus rendering ineffective the electro-magnetic function of the slider. Also, the wire, when looped away from the load beam for connecting the slider, consumes excessive height which defeats efforts to minimize the overall disk drive height.
Movement of the slider in a pitch and/or roll direction is necessary for the slider to remain a substantially constant fly height above the surface of the rotating disk of the disk drive. The slider must be free to respond to very minute deviations from a perfect plane as the disk rotates at high speed to read and write reliably the data on the magnetic recording member as well as to prevent the slider from impacting the surface of the rotating disk and thus destroying some of the magnetic disk coating and the data stored therein.
To accommodate the pitch and roll of the slider and magnetic head in response to the movement of the disk past the slider, and accordingly to maintain a constant fly height over the surface of the disk, those forces resisting the pitch and roll of the slider must be extremely small. The pitch and roll movement is primarily required due to geometric imperfections between disk stacks and actuator positioning. To accommodate the small forces and still to permit the pitch and roll movement, a small cross sectional support for the slider is used. The small cross sectional supports are weak and subject to over-stress and damage from large deformations. In addition, it is undesirable to permit excessive movement of the slider during handling and assembly of the disk drive. Accordingly, the excessive movement of the slider must be prevented in order to prevent damage to the slider, the flexure support, or the disk surface.
Accommodating all of the foregoing conditions and requirements becomes a significant undertaking when designing the load beam/slider assembly for use in a small disk drive.